C program without main function :
usually it is not possible and not even make sense to write a code without main function because program start executing from main. but for the sake of argument this can be done through MACROS.
i have not experienced it personally but people say that it is very much asked in Interviews.
In following program printf statement is also working without semicolons ' ; '
#include<stdio.h>
#define any main
void any()
{
if(! printf("this program is without main function\n") )
{
}
}